Creaseproof fabric



United States Patent 3,004,870 CREASEPROOF FABRIC Herman B. Goldstein, Cranston, R.I., assignor to Sun Chemical Corporation, Long Island City, N.Y., a corporation of Delaware No Drawing. Filed Jan. 9, 1958, Set. No. 707,873 13 Claims. (Cl. 117139.4)

This invention relates to cellulosic fabrics having durable crease and wrinkle resistance and to methods of imparting these and other properties to cellulosic fabrics.

It is known that cellulosic fabrics may be rendered crease resistant by the application thereto of a thermoset- 'ting resin in a soluble form and thereafter polymerizing the resin in the interstices of and on the surface of the fabric by the application of heat curable aminoplast resins, such as urea-aldehyde or melamine-aldehyde resins, have been used for this purpose.

The prior art creaseproofing resins, while effective for imparting satisfactory crease resistance, have suffered several disadvantages. Included among the disadvantages are stiffness, or a harsh hand and undesirable resin odor on the fabric. The most serious disadvantage of the prior art nitrogen-containing resins is that they retain chlorine (picked up when the fabric is bleached or laundered with an active chlorine-containing material). Upon subsequent heating of the fabric, as in ironing, the chlorine is released and severely degrades the fabric. The degradation by chlorine results in severe loss in tensile strength, discoloration and often destroys the fabric entirely.

The art has long sought a satisfactory solution to the problem of chlorine retention by resin-treated fabrics.

Accordingly, it is among the objects of the present invention to provide crease-resistant cellulosic fabrics which have little or no ability to retain chlorine.

It is' another object of this invention to provide creaseresistant cellulosic fabrics which have a soft hand, good tear and abrasion resistance, low odor and are resistant to shrinkage.

It is another object to provide crease-resistant cellulosic fabrics which are durable to laundering and dry cleaning.

These and other advantages of the invention will be apparent-to those skilled in the art.

The method of the invention comprises impregnating cellulosic fabric with an aqueous solution containing a 1- substituted-S,5-dimethylol-2,6-dihydrotriazin-4-one and a maleic acid catalyst, drying the fabric and curing the niazini-one to an insoluble state.

A simplified flow diagram of a process of this invention is as follows:

I Cellulosie Fabric Treatment with 1-substituted-3,5-di1nethylol- 2,6-dihydrotriazin-4-one and maleic acid catalyst Drying the Treated Fabric Curing the Treated Fabric The substituted tr1az1n-4-ones useful 111 the invention have the general formula:

wherein R is a member selected from the group consisting of alkyl, substituted alkyl, cycloaliphatic and aralkyl radicals.

The above substituted triazin-4-ones are not in themselves resin-formers, but apparently react with the hydroxyl groups of cellulose to cross-link the same. Accordingly, the fabrics treated therewith are characterized by a soft hand. Where stifiness is required in the fabric, the impregnating solution may additionally contain a resin-former which is cured along with the triazin-4-one.

The substituted triazin-4-ones are prepared by reacting in aqueous solution one mol of a primary amine of the formula RNH where R is the substituent defined above, with one mole of urea and two mols of formaldehyde. The resulting intermediate is then reacted with two mols of formaldehyde to form the l-substituted-3,5 dimethylol-Z,6-dihydrotriazin-4-one.

The reaction is preferably carried out at a temperature as low as will insure keeping the reactants in solution. The equivalents of formaldehyde such as paraformaldehyde or trioxane may be used in place of formaldehyde.

The fabric may be any cellulosic fabric, including cotton, rayon and blends containing a cellulosic material and other synthetic or natural fibers.

The substituted triazin-4-one is applied to the fabric in the form of an aqueous solution by conventional padding machinery, squeezed out and thereafter dried and cured. The solution contains about 3 to 15% by weight of substituted triazin-4-one and about 1 to 5% by Weight of maleic acid catalyst based on the weight of the substituted triazin-4-one.

The fabric is dried at a temperature of about 200 to 350 F., preferably in the range of 250 to 300 F. The

curing temperature is in the range of 280 to 400 F., preferably 300 to 350 F. The drying and curing times vary, of course, with the weight of the fabric and the efficiency of the equipment, but are generally in the range of 30 seconds to 15 minutes for the drying cycle and about one minute to 15 minutes for curing.

The amount of substituted triazin-4-one on the fabric may vary between about 3% to 20%, based on the dry weight of the fabric. Excellent crease resistance may be obtained with as little as 3%. The amount of triazinlone is determined by the concentration of the impregnating solution and also by the pick-up, which may be controlled by applying more or less pressure on the squeeze rolls.

Because the substituted triazin-4-ones are not resin formers; that is, they do not polymerize in themselves, maleic acid catalyst may be used in the impregnating solution without polymerization in the solution.

in the manufacture of the 1-substituted-3,5 dimethylol- 2,6-dihydrotriazin-4-one as disclosed herein, the product contains some impurities or lay-products, principally sodium sulfate or other salt. it has been found that the pure compounds need not be isolated, however; the impurities do not deleteriously affect the creaseproofing process or the fabric itself.

After impregnation and curing of the fabric, it is sometimes desirable to wash the fabric to remove unreacted triazin-4-one, catalyst, etc. This step is not necessary however and may be eliminated.

The following examples illustrate the practice of the invention. In the examples, all parts are by weight.

EXAMPLE I I -ethyl-3 ,5 d imethyl0l-2,6 -dihydr0triaz n-4-0ne A mixture consisting of 159 parts of urea, 168.5 parts of a 70% aqueous solution of monoethylamine, 66 parts of water and 66 parts of ice was cooled to C. To

this mixture was added 107parts of 37% formaldehyde added at temperatures not exceeding 30 C. over a period of 1.5 hours and the temperature maintained while stirring'for an-additional /2 hour. mixture was then warmed to 50 C. and 408 parts of water was removed under reduced pressure. The clear homogeneous mixture was cooled to 40 C. and 428 parts of 37% formaldehyde was added over a period of minutes. The pH of the solution was adjusted to 10-11 with a 25% aqueous solution of sodium hydroxide and then warmed to 55 60 C. and held for 1 hour. The clear almost water-white solution was cooled to 40 C. and 91 parts of water and enough sulfuric acid added to adjust to pH 7.4.

15 parts of this solution were diluted with 85 parts of water, and 0.4 part of maleic acid were added to this solution as the catalyst. A cotton fabric was impregnated with the solution, squeezed, dried at 280 F. and cured at 320 F. The fabric was then washed with an aqueous solution of 0.1% sodium lauryl sulfate, 0.2% sodium carbonate and 0.3% sodium perborate. The fabric was then rinsed, framed to width and dried. It exhibited high levels of crease resistance, retained substantially no chlorine, showed excellent shrinkage resistance and was permanent to washing and dry cleaning. The fabric had no appreciable amine odor.

7 EXAMPLE II 1-is0-pr0pyl-3,S-dimethylol-2,6-dihydrozriazin-4-one To 160 parts of urea was added 66 parts of water'and 153 parts of iso-propylamine. To this homogeneous mixture was added 66 parts of ice and cooled to 10 C. One hundred seven parts of a 37% solution of formaldehyde was carefully added over a period of 2 hours maintaining the temperature at '1520 C. The second portion of 107 parts of 37% formaldehyde was added at 25 -29 C. over a period of 1.5 hours. The remainder f the 37% formaldehyde (214 parts) was added over a period of 1.5 hours at temperatures not exceeding 30 C. and then held at 30 C. for 0.5 hour. The clear almost water-white solution was warmed to 50 C. and 408 parts of water removed under reduced pressure.

I The homogeneous solution was cooled to 40 C. and a 37% solution of formaldehyde (428 parts) was carefully added over a period of 15 minutes. After the pH of the mixture was adjusted to 10-11 with 25 aqueous sodium 7 EXAMPLE III 1-n-butyl-3,5-dimethylol-Z,6-dihydrotriazin-4-one V 32 parts of urea were dissolved in 13.2 parts water and 38.2 parts of n-butyl'amine added. To this mixture was added 13.2 parts of ice and cooled to 5 -10 C. The 37 solution of formaldehyde was added in three separate portions. Over a period of 2 hours 21.4 parts of a 37% solution of formaldehyde was added'while the temperature was maintained at 15 20 C. Another portion of 21.4 parts of 37% formaldehyde was added over a period of 1.5 hours at temperatures not exceeding 29 The reaction C. The last portion of 37% formaldehyde (42.8 parts) was added at 25 -30 C. over a period of 1.5 hours after which the temperature was held for 0.5 hour. The mixture was then warmed to 50 C. and 81.6 parts'of water was removed under reduced pressure. The almost waterwhite solution was cooled to 40 C. and 85.6 parts of a 37 solution of formaldehyde was added over. a period of 15 minutes. The hydrogen ion concentration of the mixture was "adjusted to pH 10-11 with 25% sodium hydroxide. The mixture was warmed to 55-60 C. and held for 1 hour with subsequent cooling to '40" C. and the addition of 18.2 parts of water and'enough of a 25% maleic acid solution to adjust to pH to approximately neutral.

Eight parts of the above solution were added to 92 parts water and 0.2 part maleic acid and a nylon-cotton blend impregnated therewith as in Example I. The drying temperature was 240? F. and the curing temperature 300 F. The fabric. exhibited excellent crease resistance and very low chlorine retention.

EXAMPLE IV I-cycIOhexyI -iS-dimethylol-2,6-dihydrotriazin-4-one A mixture of 159 parts of urea, 258 parts of cyclohexylamine, 66 parts of water and 66 parts of ice was cooled to 10 C. and 107 parts of a 37% solution of formaldehyde was added over a period of 1.5 hours at '1520 C. Another portion of 37% formaldehyde (107 parts) was added over a period of "1.5 hours at 2029 C, after which 214 parts of 37% formaldehyde was added over a period of 15 hours at temperatures not above 30 C. The heterogeneous mixture was allowed to separate and 408 parts of water drawn off. To the mixture was slowly added 428 parts of a 37 formaldehyde solution over'a period of 15 minutes at temperatures not exceeding 40 C. The pH was then adjusted to 10-11 with 25 sodium hydroxide and the mixture warmed to 55 60 C. and held for 1 hour after which the pH was adjusted to 7.4 with concentrated sulfuric acid. a

An aqeous-solutioncontaining 5% of the above triazin- 4-one and 0.05% maleic acid was applied to cotton as in Example I. The resulting fabric exhibited excellent crease resistance and low chlorine retention.

7 EXAMPLE v 1-benzyl-3,5-dimethyl0l-Z,6-dihydrotriazin-4-0ne To 159 parts of urea was added 66 parts of water, 285 parts of'benzylamine, 66 parts of ice. The mixture was cooled to 10 C. and 107 parts of a 37% Solution of formaldehyde was carefully added over a period of 2 hours at 15-20 C. Another portion of 107 parts of 37% formaldehyde was added over a period of 1.5 hours at 25 29 C. after which 214 parts of 37% formaldehyde was added over a period of 1.5 hours at temperatures not exceeding 30 C. The temperature was maintained at 30 C. for 0.5 hour and then warmed to 50 C. to remove 408 parts of water under reduced pressure. The mixture was then cooled to 40 C. and 428 parts of 37% formaldehyde was carefully added oved a period of 15 minutes. The hydrogen ion concentration of the mixture was adjusted to pH 10 11 with 25% sodium hydroxide and warmed to 55-60 C. for 1 hour. After the homogeneous mixture was cooled to 40 C. and 91 parts of water added, the pH was'adjusted to 7-8 with maleic acid.

A 15% solution of the above triazin-4-one containing ma.eic acid was applied to a viscose rayon-cellulose acetate blend as in Example I. The fabric showed good crease resistance and substantially no chlorine retention.

EXAMPLE VI 1 hydroxyethyl 3,5-dimethylo l-2,6-dihydr otriazin-4-one To 16 parts of urea was added 6.6 parts of water and 16.2 parts of monoethanolamine. To this homogeneous mixture was added 6.6 parts of ice and cooled to C. One hundred seven parts of 37% formaldehyde was carefully added over a period of 2 hours at 20 C. The second portion (10.7 parts) of 37% formaldehyde was added at -29 C. over a period of 1.5 hours. The remainder of 37% formaldehyde (21.4 parts) was added over a period of 1.5 hours at temperatures not exceeding C. and then held at 30 C. for 0.5 hour. The solution was warmed to 50 C. and 408 parts of water removed under reduced pressure. The mixture was then cooled to 40 C. and 428 parts of 37% formaldehyde was added over a period of 15 minutes. The pH of the mixture was then adjusted to 10-11 with 25% aqueous sodium hydroxide and the temperature increased to 55 60 C. and held for 1 hour. The solution was cooled to room temperature, and it was not neutralized immediately. Instead, when the product was diluted with water to prepare the textile treating bath, 0.8 part of maleic acid were used.

An aqueous solution of the above (containing 7% by weight of the substituted triazin-4-one) was applied to cotton as in Example I. The fabric showed high crease resistance and substantially no chlorine retention.

Additional substituted triazin-4-ones useful in the crease-proofing process of the invention include 1-n-propyl-3,5-dimethylol-2,6 dihydrotn'azin-4-one 1-isobutyl-3,5-dimethylol-2,6 dihydrotriazin-4-one l (2 chloro)ethyl-3,5-dimethylol-2,6 dihydrotriazin-4- one 1chloromethyl-3,5-dimethylol-2,6 dihydrotriazin-4-one 1 (3 chloro)propyl-3,5-dimethylol-2,6 dihydrotriazin- 4-one.

The above may be prepared in the manner disclosed above, using the appropriate amine in the reaction. The compounds may also be prepared by other processes known in the art.

The term chlorine retention as used throughout the specification refers to the objectionable chlorine released when the fabric is heated, and which damages the fabric. Thus, fabrics treated with the instant compounds probably do pick up some chlorine from bleach baths, but the chlorine is tightly held on the fabric and hence cannot damage the same. Chlorine retention therefore is measured by the amount of fabric damage as indicated by loss of strength in accordance with tests adopted by the American Association of Textile Chemists and Colorists.

While the invention has been described in terms of certain examples, such examples are to be considered illustrative rather than limiting, and it is intended to cover all modifications and embodiments that fall within the spirit and scope of the appended claims.

What is claimed is:

1. A process for creaseproofing cellulosic fabric which comprises impregnating the fabric with an aqueous solution of a l-substituted 3,5-dimethylol-2,6-dihydrotriazin- 4-one of the formula wherein R is a radical selected from the group consisting of alkyl, haloalkyl, hydroxyalkyl, cycloaliphatic and aralkyl radicals, said solution containing maleic acid, drying the fabric and curing said triazin-4-one by the application of heat.

2. The process set forth in claim 1 wherein said solution contains about 3% to 20% by weight of said triazin- 4-one and about 1% to 5% by weight of maleic acid based on the weight of said triazin-4-one.

3. The process set forth in claim 1 wherein said fabric is dried at about 200 to 350 F. and cured at about 280 to 400 F.

4. The process set forth in claim 1 wherein said fabric is dried at about 250 to 300 F. and cured at about 300 to 350 F.

5. The process set forth in claim 1 wherein said triazin- 4 one is 1-ethyl-3,5-dimethylol-2,6-dihydrotriazin-4-one.

6. The process set forth in claim 1 wherein said triazin- 4 one is 1-propyl-3,5-dimethylol-2,6-dihydrotriazin-4- one.

7. The process set forth in claim 1 wherein said triazin- 4-one is 1 cyclohexyl-3,5-dimethylol-2,6-dihydrotriazin- 4-one.

8. The process set forth in claim 1 wherein said triazin- 4 one is 1-benzyl-3,S-dimethylol-2,6-dihydrotriazin-4- one.

9. A creaseproof, non chlorine-retentive cellulosic fabric containing a heat and maleic acid cured l-substituted- 3,5 dimethylol 2,6-dihydrotriazin-4-one of the formula wherein R is a radical selected from the group consisting of alkyl, haloalkyl, hydroxyalkyl, cycloaliphatic and aralkyl radicals.

10. The fabric set forth in claim 9 wherein said triazin- 4-one is 1 ethyl-3,S-dimethylol-2,6-dihydrotriazin-4-one.

11. The fabric set forth in claim 9 wherein said triazin- 4-one is 1 propyl-3,5-dimethylol-2,6 dihydrotriazin-4- one.

12. The fabric set forth in claim 9 wherein said triazin- 4-one is 1 cycloheXyl-3,5-dimethylol-Z,6-dihydrotriazin- 4-one.

13. The fabric set forth in claim 9 wherein said triazin- 4-one is l benzyl-3,5-dimethylol-2,6-dihydrotriazin-4- one.

References Cited in the file of this patent UNITED STATES PATENTS 2,321,989 Burke June 15, 1943 2,373,135 Maxwell Apr. 10, 1945 2,373,136 Hoover et al. Apr. 10, 1945 2,641,554 Meunier et al. June 9, 1953 2,641,584 Martone June 9, 1953 2,662,872 Gagarine et al. Dec. 15, 1953 2,690,404 Spangler et a1 Sept. 28, 1954 2,826,500 Keim Mar. 11, 1958 2,898,238 Loo et al. Aug. 4, 1959 2,901,463 Hurwitz Aug. 25, 1959 2,930,106 Wrotnowski Mar. 29, 1960 OTHER REFERENCES Reid et al.: Imparting Wrinkle Resistance To Cotton Fabrics With Triazone Derivatives, October 30, 1958, at 37th National Convention, 10 pages, page 2 of interest, reprinted from American Dyestutf Reporter, vol. 48, No. 3, pages PSI-P90, Feb. 9, 1959. 

1. A PROCESS FOR CREASEPROOFING CELLULOSIC FABRIC WHICH COMPRISES IMPREGNATING THE FABRIC WITH AN AQUEOUS SOLUTION OF A 1-SUBSTITUTED 3,5-DIMETHYLOL-2,6-DIHYDROTRIAZIN4-ONE OF THE FORMULA 